1. Field of the Invention
This invention pertains to air conditioning equipment, refrigerators and freezers equipped with a liquid cooled condenser having a relief valve for the discharge of refrigerant in the event of over pressurization or failure of the relief valve. Industrial air conditioning equipment of the type used in computer rooms may contain as much as 28 lbs. by weight of refrigerant. If the relief valve should fail, the entire 28 lbs. of refrigerant could be discharged into the computer room and then into the atmosphere.
This discharge is dangerous to the health of workers in the computer room and to the general health of the population through depletion of the ozone layer. The discharge of refrigerant into computer rooms may result in destruction of computer equipment and tapes as well as premature activation of smoke detectors and fire warning systems.
These types of equipment typically have high and low pressure safety switches rated at 250 to 400 PSIG and 0 to 20 PSIG respectively which open and close depending upon the pressures in the system.
The environmental impact of such discharge is obvious and therefore there is a serious need to prevent such discharge into the atmosphere.
2. Background of the Prior Art
U.S. Pat. No. 5,140,827 shows in FIG. 1 a heat pump system 10 having a compressor C with a discharge port P and a suction port S. The discharge port P is connected to a four way valve 18.
This system contemplates automatically adding refrigerant or removing refrigerant from the heat pump depending on the temperature of the compressed refrigerant leaving the discharge port of the compressor 12.
U.S. Pat. No. 5,050,393 shows a refrigeration system FIG. 1 which induces a control device 50 including a reservoir 57 which receives liquid refrigerant from evaporator 12 through line 54.
U.S. Pat. No. 4,912,933 is directed to a transport vehicle refrigeration system, FIG. 1, which includes a reservoir 26 connected to the output of condenser 24. Further, an accumulated tank 44 is shown associated with evaporator 42.
U.S. Pat. No. 4,841,739 is directed toward an automotive air conditioning system which shows an air conditioner system having a compressor 1, a condenser 8 and an evaporator 5 connected together in the usual fashion.
A relief valve 13 is in the refrigerant deliverance line 12 which blows off high pressure refrigerant into reservoir 11. The collected refrigerant may be returned to line 12 via valve 14 under specific conditions, or the collected refrigerant may be returned via valve 15 into the suction line 6.
U.S. Pat. No. 3,487,656 describes a refrigeration system in which various magnetically operated solenoid valves, float switches, timers, etc. are employed in the operation of this system.
U.S. Pat. No. 3,353,367 discloses a refrigerant return system in which a unit 43 senses a maximum and minimum amount of refrigerant and via valves and lines returns refrigerant to the system.